the key is that penalty charges must be at a level that reflects the cost of administering them. to me �90 seems too much and is way above the average according to this article
http://news.bbc.co.uk/1/hi/business/6169539.st m
which explains it fully and, via the artlicle found via the link under the first picture 'how to claim back your penalty charges' gives advice on how to go about getting some back.
who do you bank with?
can i have a cut of your refund if this info helps you get one?